The mechanochemical production of phenyl cations through heterolytic bond scission

Tomohiro Shiraki, Charles E. Diesendruck, Jeffrey S. Moore

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

High mechanical forces applied to polymeric materials typically induce unselective chain scission. For the last decade, mechanoresponsive molecules, mechanophores, have been designed to harness the mechanical energy applied to polymers and provide a productive chemical response. The selective homolysis of chemical bonds was achieved by incorporating peroxide and azo mechanophores into polymer backbones. However, selective heterolysis in polymer mechanochemistry is still mostly unachieved. We hypothesized that highly polarized bonds in ionic species are likely to undergo heterolytic bond scission. To test this, we examined a triarylsulfonium salt (TAS) as a mechanophore. Poly(methyl acrylate) possessing TAS at the center of the chain (PMATAS) is synthesized by a single electron transfer living radical polymerization (SET-LRP) method. Computational and experimental studies in solution reveal the mechanochemical production of phenyl cations from PMA-TAS. Interestingly, the generated phenyl cation reacts with its counter-anion (trifluoromethanesulfonate) to produce a terminal trifluoromethyl benzene structure that, to the best of our knowledge, is not observed in the photolysis of TAS. Moreover, the phenyl cation can be trapped by the addition of a nucleophile. These findings emphasize the interesting reaction pathways that become available by mechanical activation.

Original languageEnglish
Pages (from-to)385-394
Number of pages10
JournalFaraday Discussions
Volume170
DOIs
Publication statusPublished - Dec 1 2014

Fingerprint

Cations
cleavage
Salts
salts
cations
Polymers
polymers
harnesses
Nucleophiles
Living polymerization
Photolysis
nucleophiles
Chemical bonds
Peroxides
peroxides
acrylates
chemical bonds
Free radical polymerization
Benzene
Polymerization

All Science Journal Classification (ASJC) codes

  • Physical and Theoretical Chemistry

Cite this

The mechanochemical production of phenyl cations through heterolytic bond scission. / Shiraki, Tomohiro; Diesendruck, Charles E.; Moore, Jeffrey S.

In: Faraday Discussions, Vol. 170, 01.12.2014, p. 385-394.

Research output: Contribution to journalArticle

Shiraki, Tomohiro ; Diesendruck, Charles E. ; Moore, Jeffrey S. / The mechanochemical production of phenyl cations through heterolytic bond scission. In: Faraday Discussions. 2014 ; Vol. 170. pp. 385-394.
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